Correctly delete replica controller

The correct way to delete a rc should be:
1. Resize the rc to 0.
2. Delete all pods in the rc.
3. Delete the rc.
So, we should use 'kubectl stop rc id' to completely delete a rc.
This command will first resize a rc to 0 and then delete all pods,
before deleting the rc.

Change-Id: I3666606f15440942c192aa81635899fa135d036d
Closes-Bug: 1424304

doc/source/dev/dev-quickstart.rst

@@ -109,7 +109,7 @@ required action is to install kubectl manually.
 
 Install binary distribution of kubectl distributed by Google::
 
-    wget https://github.com/GoogleCloudPlatform/kubernetes/releases/download/v0.7.0/kubernetes.tar.gz
+    wget https://github.com/GoogleCloudPlatform/kubernetes/releases/download/v0.11.0/kubernetes.tar.gz
     tar -xzvf kubernetes.tar.gz
     sudo cp -a kubernetes/platforms/linux/amd64/kubectl /usr/bin/kubectl
 

magnum/conductor/handlers/common/kube_utils.py

@@ -262,15 +262,15 @@ class KubeClient(object):
             return False
         return True
 
-    def rc_delete(self, master_address, name):
-        LOG.debug("rc_delete %s" % name)
+    def rc_stop(self, master_address, name):
+        LOG.debug("rc_stop %s" % name)
         try:
-            out, err = utils.trycmd('kubectl', 'delete', 'rc', name,
+            out, err = utils.trycmd('kubectl', 'stop', 'rc', name,
                                     '-s', master_address)
             if err:
                 return False
         except Exception as e:
-            LOG.error(_LE("Couldn't delete rc %(rc)s due to error %(error)s")
+            LOG.error(_LE("Couldn't stop rc %(rc)s due to error %(error)s")
                          % {'rc': name, 'error': e})
             return False
         return True

magnum/conductor/handlers/kube.py

@@ -224,7 +224,7 @@ class Handler(object):
         k8s_master_url = _retrieve_k8s_master_url(context, rc)
         if _object_has_stack(context, rc):
             # trigger a kubectl command
-            status = self.kube_cli.rc_delete(k8s_master_url, rc.name)
+            status = self.kube_cli.rc_stop(k8s_master_url, rc.name)
             if not status:
                 return None
         # call the rc object to persist in db

magnum/tests/conductor/handlers/test_kube.py

@@ -248,3 +248,27 @@ class TestKube(base.TestCase):
             self.kube_handler.rc_create({}, expected_rc)
             mock_kube_cli.rc_create.assert_called_once_with(
                 expected_master_url, expected_rc)
+
+    @patch('magnum.conductor.handlers.kube._object_has_stack')
+    @patch('magnum.conductor.handlers.kube._retrieve_k8s_master_url')
+    @patch('magnum.objects.ReplicationController.get_by_uuid')
+    def test_rc_delete_with_success(self,
+                                    mock_rc_get_by_uuid,
+                                    mock_retrieve_k8s_master_url,
+                                    mock_object_has_stack):
+        expected_master_url = 'master_address'
+        mock_rc = mock.MagicMock()
+        mock_rc.name = 'test-rc'
+        mock_rc.uuid = 'test-uuid'
+        mock_rc_get_by_uuid.return_value = mock_rc
+
+        mock_retrieve_k8s_master_url.return_value = expected_master_url
+        mock_object_has_stack.return_value = True
+        with patch.object(self.kube_handler, 'kube_cli') as mock_kube_cli:
+            mock_kube_cli.rc_stop.return_value = True
+
+            self.kube_handler.rc_delete(self.context, mock_rc.uuid)
+
+            mock_kube_cli.rc_stop.assert_called_once_with(
+                expected_master_url, mock_rc.name)
+            mock_rc.destroy.assert_called_once_with(self.context)